1. Field of the Invention
The present invention relates to a method for orienting and processing a liquid crystal display element (hereinafter abridged as LCD).
2. Description of the Prior Art
As one method for orienting liquid crystal particles in an LCD cell in a specific direction, there is a rubbing method. This rubbing method is an orienting and processing method which comprises rubbing in a specific direction an orienting film for coating a transparent electrode on a glass substrate by use of a rubbing material during production of LCD.
That is, as shown in FIG. 4, a transparent electrode 2 is formed on a glass substrate 1. An orienting film 3 is formed on the transparent electrode 2. Thereafter, a cylindrical roller 5 having a rubbing material 4 wound on the outer peripheral surface thereof with a number of fibers 4a standing upright is rotated at a high speed and at the same time, the surface of the orienting film 3 is subjected to rubbing in a specific direction. Then, the long axis of liquid crystal particles is oriented in a direction parallel with the rubbing direction. As the rubbing material 4 used for such orienting and processing by rubbing, raising clothes have been generally used in which the surface of the cloth obtained by weaving cotton, nylon fibers and the like is raised.
In the rubbing material 4 heretofore used, a number of fibers 4a are standing approximately vertically upright on the surface, as shown in FIG. 5. The orienting film 3 is subjected to rubbing at the tips of these fibers 4a. When the rubbing material 4 having such a construction as described above is used, deep and large scratches were liable to be produced in the surface of the orienting film 3 though there is somewhat difference according to kinds. Such deep and large scratches bring forth an unevenness of orientation particularly in a so-called S-TN (Super-Twisted) type LCD in which a twisting angle of a liquid crystal is set to 180.degree. or more. The scratches comprise an obstacle in providing high duty and larger display surface.